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In Diesel engines, the control of black smoke in the exhaust can be achieved by: 1) Running the engine at lower load. 2) Maintaining the injection system perfect. 3) Using Diesel fuel of higher Cetane number. Which of the above statements are correct?

In Diesel engines, the control of black smoke in the exhaust can be achieved by: 1) Running the engine at lower load. 2) Maintaining the injection system perfect. 3) Using Diesel fuel of higher Cetane number. Which of the above statements are correct? Correct Answer 1 and 2 only

Explanation:

Black smoke in the exhaust of a diesel engine indicates incomplete combustion of fuel. So,

  •  Running the engine on a lower load will lead to lower fuel consumption and hence can control the black smoke at the exhaust.

  • Delayed injection results in lower power and black smoke due to incomplete combustion of fuel during the expansion stroke. Hence if the maintain the injection system perfect, it will lead to the right time injection and hence it can control black smoke.

  • Higher cetane number diesel will mean shorter delay between injection and ignition and the better ignition quality. So, fuel will have enough time to burn subject to availability of air. Hence whether it can control black smoke emission or not cannot be concluded as it is engine dependent.

      

Related Questions

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